Enter <br> instead of <p> in text area

I am using a rich text box and currently when I press return the html created is <p> and therefore leaves a line between the two lines of text, which I do not want.
I would like to know how to get a <br> to be created instead, just as this text box does.
Does anyone know how to do it?

I know how to do it myself, but I want it so that someone who is using it can just press enter and this will happen automatically. I don't want to have to write a message telling them to press shift and enter, this is going to be tested by my mum. If I told her to press shift she wouldn't have the slightest idea what I was going on about :>

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since KeK already came up with the replace, I figured I'd approach it from a different angle. Interestingly tough, the code itself doesn't take effect until after the next keypress. I left the alert in because I felt it might be enlightening.

No, I don't think that would make much of a difference. The delay seems to be built into the iframe itself (see the post above), possibly because of the nature of the 'about:blank' doc. What may be the only way to do it without delay is to append Scripts to the iframe's document for key handling, or set the iframe's src to a document that 'includes' a *.js file that has the functions.

16 is the Shift Key - if you press Shift-Enter in the iframe edit box, it gives you a single line return.
So i was hoping that if we could trap the Enter Key, and somehow replace it with Shift+Enter, we'd be okay...
In other words:
replace event.keyCode=13 with "event.keyCode==16 AND event.keyCode=13"

Thanks for the all the help. If anyone ever does figure a simple way of getting this done you could send it to me: senda_letter@hotmail.com
For now I shall use the one suggested by knightEknight.
Thank you

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